Heat Transfer: Volume 2最新文献_第10页

Interaction Coefficient Between Ice Particles in Convective Melting of Granular Packed Bed 粒状充填床对流熔融过程中冰粒间相互作用系数

Heat Transfer: Volume 2 Pub Date : 1999-11-14 DOI: 10.1115/imece1999-1032

J. Jiang, Y. Tao

{"title":"Interaction Coefficient Between Ice Particles in Convective Melting of Granular Packed Bed","authors":"J. Jiang, Y. Tao","doi":"10.1115/imece1999-1032","DOIUrl":"https://doi.org/10.1115/imece1999-1032","url":null,"abstract":"\u0000 To numerically simulate the convective melting of packed bed it is necessary to determine the thermophysical properties or their constitutive equations. One of the most uncertain values among them is the solute interaction coefficient of solid particles, which represents the interaction force between solid particles and is equivalent to the viscosity term in Navier-Stokes equations if the dirty fluid model is applied. It was found from the previous study that the solute (solid particle) interaction coefficient, μs, characterizes the solubility such as the melting rate, the distribution of ice volume fraction, the velocity of ice particle, and the melting time. In this study, a parametric study based on the two-dimensional model for the convective melting of granular packed beds (Jiang et al. 1999) is conducted to determine the sensitivity of interaction coefficient to the model prediction. The packed bed considered here is collection of ice particles of various shapes. Warm water at a constant temperature enters horizontally the bed where melting takes place. Two cases are considered. One is to consider μs as constant, and the other is to consider it as a function of the ice volume fraction. The melting rate, fluid flow velocity and ice volume fraction distribution are discussed for different interaction coefficient values. An “optimal” interaction coefficient between ice particles is determined by comparing the simulation data with experimental data (Tao et al. 1998). It is found that the melting results are most sensitive to the value of constant interaction coefficient rather than to whether it is a constant or as a function of the ice volume fraction.","PeriodicalId":201774,"journal":{"name":"Heat Transfer: Volume 2","volume":"491 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132235121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Three-Dimensional Numerical Simulation of Convective Melting of Solid Particles in a Fluid 流体中固体颗粒对流熔融的三维数值模拟

Heat Transfer: Volume 2 Pub Date : 1999-11-14 DOI: 10.1115/imece1999-1031

Y. Hao, Y. Tao

引用次数: 0

Augmented Performance of Flow Boiling Heat Transfer in a Tube With Axial Micro-Grooves and its Augmentation Mechanisms 轴向微槽管内流动沸腾换热的增强性能及其增强机理

Heat Transfer: Volume 2 Pub Date : 1999-11-14 DOI: 10.1115/imece1999-1045

Lixin Cheng, Tingkuan Chen

引用次数: 0

The Influence of Oxygen Injection Configuration in the Performance of an Aluminum Melting Furnace 喷氧方式对熔铝炉性能的影响

Heat Transfer: Volume 2 Pub Date : 1999-11-14 DOI: 10.1115/imece1999-1052

A. Nieckele, M. Naccache, Marcos S. P. Gomes, W. Kobayashi

{"title":"The Influence of Oxygen Injection Configuration in the Performance of an Aluminum Melting Furnace","authors":"A. Nieckele, M. Naccache, Marcos S. P. Gomes, W. Kobayashi","doi":"10.1115/imece1999-1052","DOIUrl":"https://doi.org/10.1115/imece1999-1052","url":null,"abstract":"\u0000 In the present work, a numerical simulation of the 100% oxy-firing combustion process inside an industrial Aluminum Remelting Reverb Furnace is presented. A staged combustion oxy-fuel burner is being simulated. The natural gas and oxygen were injected toward the aluminum bath, which was considered as an isotherm wall at melt temperature. Two types of burners are compared. For the first case, the oxygen and natural gas jets at the burner exit are parallel to each other, while for the second burner, a divergent oxygen jet is employed. The furnace heat loss to the ambient is neglected since it is small in relation to the heat liberated by the combustion process.\u0000 The k-ε model of turbulence was selected to represent the turbulent flow field. The combustion process was determined based on the Arrhenius and Magnussen Laws, and the discrete transfer radiation model was employed to predict the radiation heat transfer. The numerical procedure was based on the Finite Volume Method.\u0000 This numerical model is utilized to determine the flame pattern, species concentration distribution, and the velocity field. The temperature distribution is very useful in the evaluation of the furnace performance. Further, critical regions associated with high temperature spots at the refractory surface were discovered. The effect of the divergent jet in the heat flux distribution at the aluminum bath is also investigated.","PeriodicalId":201774,"journal":{"name":"Heat Transfer: Volume 2","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129219729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Heat Transfer in Flow Freezing Over the Isothermal Cylinders 等温圆筒上流动冻结的传热

Heat Transfer: Volume 2 Pub Date : 1999-11-14 DOI: 10.1115/imece1999-1034

S. Sadeghipour, B. Shotorban

引用次数: 0

Slug Flow Model for Infiltration Into Fractured Porous Media 裂缝性多孔介质的段塞流模型

Heat Transfer: Volume 2 Pub Date : 1999-11-10 DOI: 10.1115/imece1999-1022

M. Martinez

引用次数: 0

The Effect of Particle Inlet Conditions on FCC Riser Hydrodynamics and Product Yields 颗粒进口条件对催化裂化提升管流体力学及产率的影响

Heat Transfer: Volume 2 Pub Date : 1999-10-11 DOI: 10.1115/imece1999-1049

S. Chang, B. Golchert, S. Lottes, Chenn Q. Zhou, A. Huntsinger, M. Petrick

{"title":"The Effect of Particle Inlet Conditions on FCC Riser Hydrodynamics and Product Yields","authors":"S. Chang, B. Golchert, S. Lottes, Chenn Q. Zhou, A. Huntsinger, M. Petrick","doi":"10.1115/imece1999-1049","DOIUrl":"https://doi.org/10.1115/imece1999-1049","url":null,"abstract":"\u0000 Essential to today’s modern refineries and the gasoline production process are fluidized catalytic cracking units. By using a computational fluid dynamics (CFD) code developed at Argonne National Laboratory to simulate the riser, parametric and sensitivity studies were performed to determine the effect of catalyst inlet conditions on the riser hydrodynamics and on the product yields. Simulations were created on the basis of a general riser configuration and operating conditions. The results of this work are indications of riser operating conditions that will maximize specific product yields. The CFD code is a three-dimensional, multiphase, turbulent, reacting flow code with phenomenological models for particle-solid interactions, droplet evaporation, and chemical kinetics. The code has been validated against pressure, particle loading, and product yield measurements. After validation of the code, parametric studies were performed on various parameters such as the injection velocity of the catalyst, the angle of injection, and the particle size distribution. The results indicate that good mixing of the catalyst particles with the oil droplets produces a high degree of cracking in the riser.","PeriodicalId":201774,"journal":{"name":"Heat Transfer: Volume 2","volume":"62 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131083103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An Accuracy Evaluation for the Madejski Splat-Quench Solidification Model Madejski飞溅淬火凝固模型的精度评价

Heat Transfer: Volume 2 Pub Date : 1999-03-01 DOI: 10.1115/imece1999-1038

S. Aceves, Sahai, A. Shapiro

{"title":"An Accuracy Evaluation for the Madejski Splat-Quench Solidification Model","authors":"S. Aceves, Sahai, A. Shapiro","doi":"10.1115/imece1999-1038","DOIUrl":"https://doi.org/10.1115/imece1999-1038","url":null,"abstract":"\u0000 Development of methods to spray form materials by precisely controlled deposition of droplets can result in new manufacturing processes which offer improved metallurgical performance and reduced production costs. These processes require a more detailed knowledge of the fluid mechanics, heat transfer and solidification that occur during droplet spreading. Previous work using computer simulations of this process have been difficult to implement and have required long running times. This paper examines the use of an alternative, simplified, method developed by Madjeski for solving for the problem of droplet spreading and solidification. These simplifications reduce the overall splat spreading and solidification problem to a closed-form differential equation. This differential equation is then solved under various conditions as reported from recent publications of experimental and numerical results of drop analysis. The results from the model are compared in terms of maximum splat diameter, minimum splat thickness, and time for the droplet spreading to reach 95% of the maximum diameter. The results indicate that the accuracy of the model can be improved by accounting for energy losses in the initial rate of droplet spreading. The model results show that the predictions of experimental results are improved to within 30% over a wide range of conditions.","PeriodicalId":201774,"journal":{"name":"Heat Transfer: Volume 2","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129345196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Moving Matrix Reactor for Biomass and Organic Waste Gasification 移动基质反应器用于生物质和有机废物气化

Heat Transfer: Volume 2 Pub Date : 1997-11-16 DOI: 10.1115/imece1997-0887

Y. Goldman, Y. Timnat, P. Arfi

{"title":"Moving Matrix Reactor for Biomass and Organic Waste Gasification","authors":"Y. Goldman, Y. Timnat, P. Arfi","doi":"10.1115/imece1997-0887","DOIUrl":"https://doi.org/10.1115/imece1997-0887","url":null,"abstract":"\u0000 An organic waste gasification scheme based on the use of a new reactor concept has been investigated. The gasifier includes an intermediate heat carrier matrix, moving opposite to the gas stream. A technical embodiment of the concept is presented and a computational model for the description of the process in the reactor is developed. The first stage of the experimental study demonstrates the possibility of a two-phase counter-flow concept as a mean of providing super-adiabatic conditions, which are expected to enhance weak exothermic reactions and endothermic gasification reactions in the reforming zone. To perform a parametric study, the mathematical model was run in a simplified case with a single source of reaction-liberated energy. Temperature profiles were obtained and from our first predictive results, one can conclude that there is a broad range of combinations of gas velocity, matrix velocity and oxygen addition to control the gasification process. A feeding system and atomization into the moving matrix is currently developed to feed the reactor with an organic solid fuel downstream of the steam addition. The next stage of the research will allow us to test the complete gasification scheme with a selected biomass material. The simulation model will permit to evaluate anticipated performance of the moving matrix reactor and thus optimization of the process.","PeriodicalId":201774,"journal":{"name":"Heat Transfer: Volume 2","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125139021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

An Experimental Study of Upward Flame Spread in a Vertical Corner Wall Fire 垂直角墙火灾火焰向上蔓延的实验研究

Heat Transfer: Volume 2 Pub Date : 1997-11-16 DOI: 10.1115/imece1997-0871

A. Powell, A. Kulkarni

{"title":"An Experimental Study of Upward Flame Spread in a Vertical Corner Wall Fire","authors":"A. Powell, A. Kulkarni","doi":"10.1115/imece1997-0871","DOIUrl":"https://doi.org/10.1115/imece1997-0871","url":null,"abstract":"\u0000 This paper presents results of an experimental investigation of upward flame spread on a vertical corner wall. The corner wall flame spread phenomenon differs from that for a plain vertical wall primarily because of the radiative and flow interaction between the walls. An experimental apparatus, capable of being set at corner angles of 60°, 90°, and 135° was designed and constructed. Samples, measuring 1.20 m by 0.30 m, of plywood, particle board, and hardboard were tested. Three burner configurations were used during experimentation — an arrow configuration, a line configuration, and a point source. Flame height as a function of time was measured during each run. Several trends were observed including — the significance of the burner configuration when determining flame shapes; the relationship between radiative interaction and different corner angles; and the capability of each material to sustain flame growth once the burner was turned off. Also, the pyrolysis front was noted at the conclusion of each test run using the charred region apparent on the sample, which revealed the dependence of the shape of pyrolysis front on the burner configuration. The study allows insight into various aspects of corner fire spread and provides data for validating flame spread models.","PeriodicalId":201774,"journal":{"name":"Heat Transfer: Volume 2","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128919296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1